Unfortunately, cracking is pretty common in concrete, especially during the first 30 days, while itâs curing. There are a number of reasons why concrete cracks. The most common is because concrete shrinks as the excess water evaporates and it hardens. Concrete can also crack if it dries too quickly. Weather conditions â extreme temperatures, rapid temperature changes or conditions that are too wet or too dry â also play a major factor in how well concrete cures. When the width of a crack exceeds 1/4â in width, it is probably time to seek professional assistance.
Knot (unit) The knot (/nÉt/) is a unit of speed equal to one nautical mile (1.852 km) per hour, approximately 1.151 mph. The ISO Standard symbol for the knot is kn. The same symbol is preferred by the IEEE; kt is also common. The knot is a non-SI unit that is accepted for use with the SI.
The answer is 1.15077944802. We assume you are converting between mile/hour and knot. You can view more details on each measurement unit: mph or knots. The SI derived unit for speed is the meter/second. 1 meter/second is equal to 2.23693629205 mph, or 1.94384449244 knots. Note that rounding errors may occur, so always check the results. Use this page to learn how to convert between miles/hour and knots. Type in your own numbers in the form to convert the units!